Conventionally, absorbent articles such as absorbent pads for light incontinence that are used in disposable diapers by being attached to the inner sides of the diapers use an absorbent sheet in which particles of a highly absorbent resin or the like are sandwiched between and fixed to two sheet members of nonwoven fabric or the like. In manufacturing of such an absorbent sheet, particles of the highly absorbent resin are supplied onto one of the sheet members that is being conveyed at a constant speed, and then the other sheet member is placed on and bonded to the sheet member being conveyed.
In a manufacturing apparatus disclosed in Japanese Patent Application Laid-Open No. 2000-327127 (Document 1), a garnet cylinder that supplies pulp fiber is provided above absorbent paper that is running with a mesh belt. The garnet cylinder has saw teeth in its circumference surface. Rotation of the garnet cylinder causes the saw teeth to scrape pulp fiber that is fed from a supply belt by a predetermined amount. The scraped pulp fiber is moved downward by the rotation of the garnet cylinder and supplied onto the running absorbent paper.
With the manufacturing apparatus of Document 1, however, if the number of revolutions of a servomotor on the supply belt increases in proportion to the running speed of the mesh belt, the amount of the pulp fiber to be supplied will not increase in proportion to the running speed of the mesh belt in a region where the running speed of the mesh belt is high, and accordingly will be less than the expected amount that is determined on the assumption that the amount of pulp fiber supplied increases in proportion to the running speed.
In view of this, the manufacturing apparatus of Document 1 controls the number of revolutions of the servomotor on the supply belt independently of the running speed of the mesh belt such that the supply curve of the pulp fiber is proportional to the running speed of the mesh belt. Document 1, however, discloses a technique for controlling the supply belt or the like, assuming a manufacturing apparatus in which the garnet cylinder is provided with, for example, a screw and the supply belt for supplying pulp fiber or the like. It thus has failed to disclose a technique of control performed by apparatuses with other configurations.